<!DOCTYPE html>
<html lang="zh-CN">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>demo02</title>
</head>
<style>
    .container{
        height: 600px;
        width: 100%;
        background-color: rgba(200, 235, 61, 0.586); 
           }
</style>
<body>
    <h1>demo02</h1>
    <div class="container"></div>
</body>
</html>